1. Field of the Invention
The present invention relates to a support assembly for shelving of the type comprising a shelf supporting bracket having a rearwardly projecting tongue for interfitting in a complementary outwardly facing channelled groove in an upright, the groove having spaced-apart front and rear retaining faces and in which the bracket is retained at a predetermined height in the upright.
2. Description of Prior Art
Support assemblies for shelving of this type are already known. One such assembly is shown and described in Danish Patent Specification No. 128977. This specification describes a support assembly for shelving comprising a shelf bracket having a side mounted male slide member for fitting into a H-section rail. A cranked wedge is provided for locking the slide member in the rail. The wedge is connected to the slide member by a coil spring extending between the top of the leg and the top of the slide member. When a downward loading force is applied to the shelf bracket the wedge is intended to react between the rail and the slide member to lock the slide in position in the rail.
This known assembly suffers from several disadvantages. Firstly, the wedge is particularly adapted to resist downward loading forces on the bracket and does not effectively resist sidewardly directed forces which tend to dislodge the slide member from the H-section rail. Further, because of the arrangement of the spring, height adjustment of the bracket relative the upright is difficult. The rail must be positioned so that it is possible to insert a gripping means into the rail to pull the spring upwardly to release the wedge and hence allow upward and downward movement of the slide member in the rail. Additionally, because the groove in the rail is visible when viewed from the side the support assembly is not acceptable in most applications from an aesthetic point of view.
Other support assemblies are known in which the shelf support bracket incorporates cam means which allow height adjustment of the bracket in one orientation and resist a downward load applied to the bracket in another orientation. Generally retaining means in addition to the cam members are required to maintain the brackets in position. In some cases these retaining means comprises a ledge formed on the rear of the bracket and engagable in complementary slots formed in the rear wall of the channelled upright. These support assemblies suffer from the disadvantage that if an upwardly directed load is applied accidentally to the bracket the cam members and ledge become disengaged and the support bracket is then free to slide down the upright, collapsing the assembly.